package cn.shenning.list;
import java.util.HashMap; 
import java.util.Hashtable; 
import java.util.Iterator; 
import java.util.Map; 
import java.util.TreeMap; 
public class HashMaps { 
	public static void main(String[] args) { 
		Map<String, String> map = new HashMap<String, String>(); 
		map.put("a", "aaa"); 
		map.put("b", "bbb"); 
		map.put("c", "ccc"); 
		map.put("d", "ddd"); 
		Iterator<String> iterator = map.keySet().iterator(); 
		while (iterator.hasNext()) { 
			Object key = iterator.next(); 
			System.out.println("map.get(key) is :" + map.get(key)); 
		} 
		// 定义HashTable,用来测试 
		Hashtable<String, String> tab = new Hashtable<String, String>(); 
		tab.put("a", "aaa"); 
		tab.put("b", "bbb"); 
		tab.put("c", "ccc"); 
		tab.put("d", "ddd"); 
		Iterator<String> iterator_1 = tab.keySet().iterator(); 
		while (iterator_1.hasNext()) { 
			Object key = iterator_1.next(); 
			System.out.println("tab.get(key) is :" + tab.get(key)); 
		} 
		TreeMap<String, String> tmp = new TreeMap<String, String>(); 
		tmp.put("a", "aaa"); 
		tmp.put("b", "bbb"); 
		tmp.put("c", "ccc"); 
		tmp.put("d", "cdc"); 
		Iterator<String> iterator_2 = tmp.keySet().iterator(); 
		while (iterator_2.hasNext()) { 
			Object key = iterator_2.next(); 
			System.out.println("tmp.get(key) is :" + tmp.get(key)); 
		} 
	} 
} 